Table 5 Comparison of the pre- and postoperative features between OA progression and non-progression groups
|  | OA progression (−) N = 26 (SD or %) | OA progression (+) N = 4 (SD or %) | P value |
|---|---|---|---|
Age | 25.0 (10.2) | 17.5 (6.4) | .167 |
Gender, male/ female | 6 (23.1)/ 20 (76.9) | 2 (50)/ 2 (50) | .284 |
BMI | 23.4 (3.7) | 24.8 (2.5) | .478 |
Follow-up, year | 4.8 (2.9) | 6.2 (3.4) | .379 |
Reccurent / habitual | 20 (76.9)/ 6 (23.1) | 4 (100)/ 0 (0) | .557 |
Preoperative | |||
 Kujala score | 61.5 (11.6) | 61.2 (13.0) | .964 |
 Congruence angle, degree | 47.0 (23.5) | 43.0 (9.6) | .745 |
 Sulcus angle, degree | 149.1 (14.1) | 138.5 (4.2) | .150 |
 Tilting angle, degree | 44.5 (25.6) | 23.5 (37.0) | .117 |
 ISR | 1.18 (0.25) | 1.27 (0.23) | .485 |
 Lateral patella displacement, mm | 21.2 (11.0) | 15.9 (5.0) | .352 |
 TTTG | 19.4 (3.5) | 20.9 (2.7) | .436 |
 Iwano OA grade (0/1/2/3/4), n | 14/8/2/1/1 | 3/1/0/0/0 | 1.00 |
Postoperative | |||
 Kujala score | 93.8 (6.6) | 97.5 (2.1) | .274 |
 Congruence angle, degree | −5.5 (24.0) | 27.0 (22.0) | .017 |
 Sulcus angle, degree | 148.3 (14.1) | 139.5 (3.9) | .233 |
 Tilting angle, degree | 16.8 (7.8) | 17.0 (7.4) | .964 |
 ISR | 1.06 (0.20) | 1.19 (0.16) | .233 |
 Lateral patella displacement, mm | 1.1 (3.0) | 6.7 (2.2) | .001 |
 TTTG | 14.5 (3.1) | 16.6 (2.9) | .209 |
 Iwano OA grade (0/1/2/3/4), n | 14/10/2/0/0 | 0/2/2/0/0 | .018 |